1. Field of the Invention
The present invention relates to a liquid pressure control unit used for a vehicular anti-lock brake apparatus.
2. Description of the Related Art
One of various kinds of the vehicular anti-lock brake apparatuses is constituted by a single liquid pressure control unit in which an electric motor to drive a pump, a flow passage control purpose electromagnetic valve, a power supply equipment to cause a current to flow into the electric motor are integrally assembled to a pump block into which a pump to suck a brake liquid is incorporated (built), as disclosed in a Japanese Patent Application First Publication No. Heisei 6-122364 published on May 6, 1994 (which corresponds to a U.S. Pat. No. 5,449,226 issued on Sep. 12, 1995). This previously proposed liquid pressure control unit is constituted by a pump block formed of a metal having an electric conductivity such as made of an aluminum alloy material and on an internal of which a pump or an electromagnetic valve is housed, a motor block attached on one side surface of the pump block and in which an electric motor is incorporated, and a power supply block attached onto the other side of the pump block and into which an electronic controller to control a current flow through the motor is housed. Then, positive (pole) portions of the power supply block and the motor block are interconnected together via a penetrating hole formed on a pump housing. On the other hand, negative (pole) portions of both of the power supply block and the motor block are interconnected via the pump housing as a power supply passage. The negative pole portion of the power supply block and the negative pole portion of the motor block are connected by means of a screwing.
In the above-described previously proposed liquid pressure control unit, both of the negative pole portions of the power supply block and of the motor block are connected to the pump block by means of the screwing, respectively. However, this screwing is carried out onto the pump block from both insides of the power supply block and the motor block. Hence, with an opening for the screwing previously formed on each of the power supply block and the motor block, the screwing of the negative pole portions is carried out through each opening during the mutual coupling of each block. It is, at a final stage of assembly, necessary to cover each opening with a lid. Therefore, it becomes difficult to assembly these respective blocks into the liquid pressure control unit. In addition, once the negative pole portions are fixed to the corresponding blocks, it becomes difficult to disassemble again during a replacement of terminals. Hence, if the blocks are forcibly disassembled, a breakage or a deformation thereof becomes easy to occur. It, then, becomes difficult to reuse the liquid pressure control unit described above.